Plasma gelsolin modulates the production and fate of IL-1β-containing microparticles following high-pressure exposure and decompression

Plasma gelsolin (pGSN) levels fall in association with diverse inflammatory conditions. We hypothesized pGSN would decrease due to the stresses imposed by high pressure and subsequent decompression, and repletion would ameliorate injuries in a murine decompression sickness (DCS) model. Research subjects were found to exhibit a modest decrease in pGSN level while at high pressure and a profound decrease after decompression. Changes occurred concurrent with elevations of circulating microparticles (MPs) carrying interleukin (IL)-1β. Mice exhibited a comparable decrease in pGSN after decompression along with elevations of MPs carrying IL-1β. Infusion of recombinant human (rhu)-pGSN into mice before or after pressure exposure abrogated these changes and prevented capillary leak in brain and skeletal muscle. Human and murine MPs generated under high pressure exhibited surface filamentous (F-) actin to which pGSN binds, leading to particle lysis. Additionally, human neutrophils exposed to high air pressure exhibit an increase in surface F-actin that is diminished by rhu-pGSN resulting in inhibition of MPs production. Administration of rhu-pGSN may have benefit as prophylaxis or treatment for DCS.

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Microparticle-induced vascular injury in mice following decompression is inhibited by hyperbaric oxygen: effects on microparticles and interleukin-1β

Journal of Applied Physiology ◽

10.1152/japplphysiol.01109.2018 ◽

2019 ◽

Vol 126 (4) ◽

pp. 1006-1014 ◽

Cited By ~ 1

Author(s):

Stephen R. Thom ◽

Veena M. Bhopale ◽

Ming Yang

Keyword(s):

High Pressure ◽

Hyperbaric Oxygen ◽

Decompression Sickness ◽

Interleukin 1Β ◽

Vascular Injuries ◽

Pyrin Domain ◽

Oxygen Effects ◽

Circulating Microparticles ◽

Inflammatory Processes ◽

High Concentrations

Hyperbaric oxygen (HBO2) became a mainstay for treating decompression sickness (DCS) because bubbles are associated with the disorder. Inflammatory processes including production of circulating microparticles (MPs) have now been shown to occur with DCS, leading to questions regarding pathophysiology and the role for HBO2. We investigated effects of HBO2 on mice exposed to 790 kPa air pressure for 2 h, which triggers elevations of MPs ladened with interleukin (IL)-1β that cause diffuse vascular injuries. Exposure to 283 kPa O2 (HBO2) inhibited MP elevations at 2 h postdecompression by 50% when applied either prophylactically or as treatment after decompression, and the MP number remained suppressed for 13 h in the prophylactic group. Particle content of IL-1β at 2 h postdecompression was 139.3 ± 16.2 [means ± SE; n = 11, P < 0.05) pg/million MPs vs. 8.2 ± 1.0 ( n = 15) in control mice, whereas it was 31.5 ± 6.1 ( n = 6, not significant vs. control (NS)] in mice exposed to HBO2 prophylactically, and 16.6 ± 6.3 ( n = 7, NS) when HBO2 was administered postdecompression. IL-1β content in MPs was similar in HBO2-exposed mice at 13 h postdecompression. HBO2 also inhibited decompression-associated neutrophil activation and diffuse vascular leak. Immunoprecipitation studies demonstrated that HBO2 inhibits high-pressure-mediated neutrophil nucleotide-binding domain, leucine-rich-containing family, pyrin domain-containing-3 inflammasome oligomerization. Furthermore, MPs isolated from decompressed mice cause vascular injuries when injected into naïve mice, but if decompressed mice were exposed to HBO2 before MP harvest, vascular injuries were inhibited. We conclude that HBO2 impedes high-pressure/decompression-mediated inflammatory events by inhibiting inflammasome formation and IL-1β production. NEW & NOTEWORTHY High pressure/decompression causes vascular damage because it stimulates production of microparticles that contain high concentrations of interleukin-1β, and hyperbaric oxygen can prevent injuries.

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Provocative decompression causes diffuse vascular injury in mice mediated by microparticles containing interleukin-1β

Journal of Applied Physiology ◽

10.1152/japplphysiol.00620.2018 ◽

2018 ◽

Vol 125 (4) ◽

pp. 1339-1348 ◽

Cited By ~ 4

Author(s):

Stephen R. Thom ◽

Veena M. Bhopale ◽

Kevin Yu ◽

Ming Yang

Keyword(s):

High Pressure ◽

Cell Activation ◽

Decompression Sickness ◽

Ambient Pressure ◽

Activation Parameters ◽

Vascular Damage ◽

Interleukin 1Β ◽

Inflammasome Activation ◽

Activation Process ◽

Circulating Microparticles

Inflammatory mediators are known to be elevated in association with decompression from elevated ambient pressure, but their role in tissue damage or overt decompression sickness is unclear. Circulating microparticles (MPs) are also known to increase, and because interleukin (IL)-1β is packaged within these particles, we hypothesized that IL-1β was responsible for tissue injuries. Here, we demonstrate that elevations of circulating MPs containing up to ninefold higher concentrations of IL-1β occur while mice are exposed to high air pressure (790 kPa), whereas smaller particles carrying proteins specific to exosomes are not elevated. MPs number and intra-particle IL-1β concentration increase further over 13 h post decompression. MPs also exhibit intra-particle elevations of tumor necrosis factor-α, caspase-1, inhibitor of κB kinase-β, and inhibitor of κB kinase-γ, and elevated IL-6 is adsorbed to the surface of MPs. Contrary to lymphocytes, neutrophil nucleotide-binding oligomerization domain-like receptor, pyrin domain containing 3 (NLRP3) inflammasome oligomerization and cell activation parameters occur during high pressure exposure, and additional evidence for activation is manifested post decompression. Diffuse vascular damage, although not apparent immediately post decompression, was present 2 h later and remained elevated for at least 13 h. Prophylactic administration of an IL-1β receptor inhibitor or neutralizing antibody to IL-1β inhibited MPs elevations, increases of all MPs-associated pro-inflammatory agents, and vascular damage. We conclude that an auto-activation process triggered by high pressure stimulates MPs production and concurrent inflammasome activation, and IL-1β is a proximal factor responsible for further cytokine production and decompression-associated vascular injuries. NEW & NOTEWORTHY Elevations in circulating microparticles due to decompression have been documented in humans and animals. This report shows that intra-particle interleukin-1β causes vascular damage that can be abrogated by interventions directed against this cytokine.

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Microparticle and interleukin-1β production with human simulated compressed air diving

Scientific Reports ◽

10.1038/s41598-019-49924-1 ◽

2019 ◽

Vol 9 (1) ◽

Cited By ~ 1

Author(s):

Kaighley D. Brett ◽

Nathan Z. Nugent ◽

Noelle K. Fraser ◽

Veena M. Bhopale ◽

Ming Yang ◽

...

Keyword(s):

High Pressure ◽

Repeated Measures ◽

Sea Water ◽

Decompression Sickness ◽

Ex Vivo ◽

Ambient Air ◽

Air Pressure ◽

Research Subjects ◽

Repeated Measures Anova ◽

Gas Pressures

Abstract Production of blood-borne microparticles (MPs), 0.1–1 µm diameter vesicles, and interleukin (IL)-1β in response to high pressure is reported in lab animals and associated with pathological changes. It is unknown whether the responses occur in humans, and whether they are due to exposure to high pressure or to the process of decompression. Blood from research subjects exposed in hyperbaric chambers to air pressure equal to 18 meters of sea water (msw) for 60 minutes or 30 msw for 35 minutes were obtained prior to and during compression and 2 hours post-decompression. MPs and intra-particle IL-1β elevations occurred while at pressure in both groups. At 18 msw (n = 15) MPs increased by 1.8-fold, and IL-1β by 7.0-fold (p < 0.05, repeated measures ANOVA on ranks). At 30 msw (n = 16) MPs increased by 2.5-fold, and IL-1β by 4.6-fold (p < 0.05), and elevations persisted after decompression with MPs elevated by 2.0-fold, and IL-1β by 6.0-fold (p < 0.05). Whereas neutrophils incubated in ambient air pressure for up to 3 hours ex vivo did not generate MPs, those exposed to air pressure at 180 kPa for 1 hour generated 1.4 ± 0.1 MPs/cell (n = 8, p < 0.05 versus ambient air), and 1.7 ± 0.1 MPs/cell (p < 0.05 versus ambient air) when exposed to 300 kPa for 35 minutes. At both pressures IL-1β concentration tripled (p < 0.05 versus ambient air) during pressure exposure and increased 6-fold (p < 0.05 versus ambient air) over 2 hours post-decompression. Platelets also generated MPs but at a rate about 1/100 that seen with neutrophils. We conclude that production of MPs containing elevated concentrations of IL-1β occur in humans during exposure to high gas pressures, more so than as a response to decompression. While these events may pose adverse health threats, their contribution to decompression sickness development requires further study.

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Mast Cell Tryptase Potentiates Neutrophil Extracellular Trap Formation

Journal of Innate Immunity ◽

10.1159/000520972 ◽

2021 ◽

pp. 1-14

Author(s):

Gunnar Pejler ◽

Sultan Alanazi ◽

Mirjana Grujic ◽

Jeremy Adler ◽

Anna-Karin Olsson ◽

...

Keyword(s):

Neutrophil Extracellular Trap ◽

Human Neutrophils ◽

Functional Communication ◽

Extracellular Milieu ◽

Extracellular Traps ◽

Inflammatory Conditions ◽

Histone 3 ◽

Activated Neutrophils ◽

Core Histones

Previous research has indicated an intimate functional communication between mast cells (MCs) and neutrophils during inflammatory conditions, but the nature of such communication is not fully understood. Activated neutrophils are known to release DNA-containing extracellular traps (neutrophil extracellular traps [NETs]) and, based on the known ability of tryptase to interact with negatively charged polymers, we here hypothesized that tryptase might interact with NET-contained DNA and thereby regulate NET formation. In support of this, we showed that tryptase markedly enhances NET formation in phorbol myristate acetate-activated human neutrophils. Moreover, tryptase was found to bind vividly to the NETs, to cause proteolysis of core histones and to cause a reduction in the levels of citrullinated histone-3. Secretome analysis revealed that tryptase caused increased release of numerous neutrophil granule compounds, including gelatinase, lactoferrin, and myeloperoxidase. We also show that DNA can induce the tetrameric, active organization of tryptase, suggesting that NET-contained DNA can maintain tryptase activity in the extracellular milieu. In line with such a scenario, DNA-stabilized tryptase was shown to efficiently degrade numerous pro-inflammatory compounds. Finally, we showed that tryptase is associated with NET formation in vivo in a melanoma setting and that NET formation in vivo is attenuated in mice lacking tryptase expression. Altogether, these findings reveal that NET formation can be regulated by MC tryptase, thus introducing a novel mechanism of communication between MCs and neutrophils.

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Omega-3 Polyunsaturated Fatty Acids: Benefits and Endpoints in Sport

Nutrients ◽

10.3390/nu11010046 ◽

2018 ◽

Vol 11 (1) ◽

pp. 46 ◽

Cited By ~ 30

Author(s):

Maria Gammone ◽

Graziano Riccioni ◽

Gaspare Parrinello ◽

Nicolantonio D’Orazio

Keyword(s):

Skeletal Muscle ◽

Fatty Acids ◽

Polyunsaturated Fatty Acids ◽

Metabolic Response ◽

Muscle Metabolism ◽

Omega 3 ◽

Cellular Functions ◽

Inflammatory Conditions ◽

Inflammatory Processes ◽

And Performance

The influence of nutrition has the potential to substantially affect physical function and body metabolism. Particular attention has been focused on omega-3 polyunsaturated fatty acids (n-3 PUFAs), which can be found both in terrestrial features and in the marine world. They are responsible for numerous cellular functions, such as signaling, cell membrane fluidity, and structural maintenance. They also regulate the nervous system, blood pressure, hematic clotting, glucose tolerance, and inflammatory processes, which may be useful in all inflammatory conditions. Animal models and cell-based models show that n-3 PUFAs can influence skeletal muscle metabolism. Furthermore, recent human studies demonstrate that they can influence not only the exercise and the metabolic response of skeletal muscle, but also the functional response for a period of exercise training. In addition, their potential anti-inflammatory and antioxidant activity may provide health benefits and performance improvement especially in those who practice physical activity, due to their increased reactive oxygen production. This review highlights the importance of n-3 PUFAs in our diet, which focuses on their potential healthy effects in sport.

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High Pressure Processing and Water Holding Capacity of Sea Bass Skeletal Muscle

Journal of Aquatic Food Product Technology ◽

10.1080/10498850.2013.809831 ◽

2015 ◽

Vol 24 (8) ◽

pp. 740-751 ◽

Cited By ~ 4

Author(s):

Xiaolan Shang ◽

Anjun Liu ◽

Jie Zheng ◽

Ping Wang ◽

Shi Yin

Keyword(s):

Skeletal Muscle ◽

High Pressure ◽

Sea Bass ◽

High Pressure Processing ◽

Water Holding Capacity ◽

Water Holding

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A method for high-purity isolation of neutrophil granulocytes for functional cell migration assays

Turkish Journal of Biochemistry ◽

10.1515/tjb-2019-0089 ◽

2019 ◽

Vol 44 (6) ◽

pp. 810-821

Author(s):

Edibe Avci ◽

Yeliz Z. Akkaya-Ulum ◽

Digdem Yoyen-Ermis ◽

Gunes Esendagli ◽

Banu Balci-Peynircioglu

Keyword(s):

Flow Cytometry ◽

Cell Migration ◽

Neutrophil Migration ◽

Cost Effective ◽

In Vitro Assays ◽

Human Neutrophils ◽

Neutrophil Granulocytes ◽

Inflammatory Conditions ◽

Migration Analysis

Abstract Background Neutrophil-mediated killing of pathogens is one of the most significant functions of the primary defense of the host. Neutrophil activity and migration play a key role in inflammatory conditions. To gain insights into the interactions between neutrophils and neutrophil migration-related disorders, a large number of sophisticated methods have been developed. The technical limitations of isolating highly purified neutrophil populations, minimizing both cell death and activation during the isolation process, and the short lifespan of neutrophils present challenges for studying specific functions of neutrophils in vitro. In this study, we aimed to evaluate a separation medium-based density gradient method to obtain highly purified neutrophil populations and combined this protocol with a model for studying neutrophil migration in-vitro. Materials and methods Human granulocytes were isolated using Lympholyte-poly solution. The purity and viability of isolated neutrophils were assessed by flow cytometry and morphological analysis. Neutrophil activation was confirmed by immunocytochemistry. Lastly, filter assay was performed to measure neutrophil chemotaxis. Results and discussion All validation experiments revealed that this method was capable of generating a highly purified neutrophil population for further functional in-vitro assays. Consequently, this study demonstrates a quick, cost effective, and easy-to-follow model, and may be a significant alternative to isolation methods that need extra subsequent steps such as flow cytometry-based cell sorting for reaching highly purified neutrophil population. Conclusion The suggested combination of methods for the isolation and cell migration analysis of human neutrophils is highly recommended to use for disease models involving neutrophil migration such as autoinflammatory disorders.

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Human Plasma Gelsolin Inhibits Cellular Responses to Platelet Activating Factor (PAF).

Blood ◽

10.1182/blood.v106.11.3568.3568 ◽

2005 ◽

Vol 106 (11) ◽

pp. 3568-3568

Author(s):

Teresia A. Magnuson-Osborn ◽

Claes Dahlgren ◽

John H. Hartwig ◽

Thomas P. Stossel

Keyword(s):

Platelet Activating Factor ◽

Actin Binding ◽

Major Surgery ◽

Human Neutrophils ◽

Dependent Manner ◽

Cellular Activation ◽

Blood Concentrations ◽

Plasma Gelsolin ◽

Molar Excess

Abstract Gelsolin is a highly conserved intracellular actin-binding protein with an extracellular isoform named plasma gelsolin (pGSN). Relatively high (250 mg /L) blood concentrations of pGSN decrease in response to trauma, major surgery, sepsis, burns, ionizing radiation, and hyperoxia. Depletion of pGSN to a critical (~20%) level precedes and predicts complications of primary injuries such as lung permeability changes, ARDS, assisted ventilation and death. Administration of recombinant pGSN ameliorates such complications and reduces mortality in animal models. A proposed mechanism for pGSN’s protective effects is that it inhibits inflammatory mediators generated during primary injuries, since pGSN binds bioactive mediators, including lysophospatidic acid (LPA) and endotoxin in vitro. Because of its structural similarity we hypothesized that plasma gelsolin binds also to the potent lipid mediator platelet activating factor (PAF) and report here on the inhibition of PAF-induced cellular activation. Recombinant pGSN inhibited PAF-induced P-selectin up-regulation by human platelets as measured by flow cytometry. A ten- to 40-fold molar excess (0.5–20 μM) of pGSN over PAF inhibits P-selectin expression by 40 to 80%. The concentrations of plasma gelsolin used approximate the ~2–3 μM concentrations in plasma, and the molar excess of pGSN over PAF is probably greater in biological systems, where PAF has nanomolar affinity for its receptor. pGSN also inhibited PAF-induced superoxide anion (O2-) production (measured by chemiluminescence) of human neutrophils (PMN) in a concentration-dependent manner. The inhibition was up to 80% at a concentration of 10 μM (tenfold molar excess over PAF). A phospholipid-binding peptide derived from pGSN (QRLFQVKGRR) also inhibited PAF-mediated O2- generation by PMN. The inhibition was 65% at a 1:1 molar ratio (1 μM). In conclusion pGSN interferes with PAF-induced cellular activation in vitro, suggesting a mechanism for the protective role of plasma gelsolin that has been observed in vivo.

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